Help!
I have a 2000 S Type 4.0
Owned since new, dealer maintained, 100K miles, garaged.
Car is like new/flawless (except for the minor detail of the no start thing!!!!)

Recently (6-9 months), it began intermittently not starting.
Cranks fine, just no start (not even a hint of wanting to....).
No pattern or other symptoms.
Will start fine 9 out of ten times, then not.
May start OK minutes, hours, or not for days later.
Dealer could not find problem (no codes, could not get symptom to repeat).
New battery.

This is a tragedy, great car is useless because it will strand you.
Has anyone else had this issue?
What are possibilities?
I don't want to randomly begin changing parts....

I will mention one thing, horn does not beep when I set alarm/lock.
Don't think it is related as that existed long before the problem began.

 

What are you doing when it does start and how long must you wait? Do you continue to crank until it starts?

We are seeing on the xk8 & xj8 a similar problem and it is related to the shifter selector switch. The next time it does not start move the shifter from “P” to “N” and give it a try. Remember that with the selector in “N” the car will move without applying the brakes.

 

^Excellent point.

 

I thought I understood.... until

Now I'm confused! If it starts 9 out of 10 how can it strand you?

Shift lever is worth trying and maybe after that the CMP (camshaft sensor) - any competent tech can scope it.

Thing is... they're going to have big troubles if it won't fail when they look at it.

 

it has 2 camshaft sensors and they are different from each other so you can not try it on one bank then the other, plus they are expensive around £100 each over here, mine is showing up that on the code reader also mine is missing really bad when cruising at any speed, plus it has decided not to start on 2 occasions recently, I am trying to find out if there is a way of finding out which one is at fault, any ideas anyone

 

Too clarify, when it does not start, it will not start for hours/days.
Not sure exactly, because it is not my only vehicle and I just randomly try it over the course of days and/or weeks.
It will strand you because it will take hours/days to finally start.
Have tried the shift lever thing....
Thanks for the thoughts....

 

Much more likely to be CKP (crankshaft sensor) or a wiring/connector problem.

When it cranks but does not start, what does the PATS light (top middle of dash) do? Watch it when the car starts so you know the normal pattern. When it won't start watch that light as you crank and for 2-3 mins in case it flashes a code (short & long flashes) and note it carefully if so.

 

I had a similar sounding problem, with my 2005 S type 4.2.

It was the crank sensor. Pretty cheap fix ($250 I think at my local mechanic).

 

The PATS light shines solid when cranking, then dark when not.
Flashes when alarm is set.

Would the CKP only be an issue when starting (with no symptoms while running)?
It runs perfect once started.

Thanks
Ken

 

When it does start it is usually instantaneous (normal), sometimes it may take 5 seconds, but no more.
When it does not start, it could crank for hours without even a cough....
Have tried all types of playing" with shifter while trying to start.
Thanks for the thoughts

 

When your crank sensor went, did only effect starting or was there other symptoms beforehand (ie; rough idle, stalling, ect)?

Thanks
Ken

 

NEW INFO!?!?

After it refusing to start for the last two weeks, I decided to try a couple things;
1- pull fuse for PATS (no crank with fuse pulled, crank but stil no start when replaced).
2- Pulled positive battery terminal and left disconnected for about ten minutes. IT STARTED right away when replaced. Unfortunately, it would not start again the next morning, but then today it started. again...

Maybe the battery thing was a coincidence or did it reset something?
I am open (and thankful) for anyones thoughts.
Ken

 

Check your mail!

 

When my CKP went bad, it ran great, just wouldn't start.

 

Well what did we find?

 

mine is the cam shaft sensor according to the fault code (on my mates reader) and going to sort it out when get home from vacation next week

John
from a sunny Greek island

 

I had the same problem and my local Jag dealer finally worked it out. With my Jag it turned out to be in the security system and the ignition switch. We replaced the ignition switch, not a hint of a problem since. Apparently the switch did not read the key code on an intermittent basis. They said another similar case they dealt with was the key itself. Hope this helps.